Feeding device for furnaces



oct.' 20, 1925. 1,551,722

A. PASTRNAK FEEDING mvlcxaI Fon Funmrcgs Filed Feb. 7, 1925 1 PatentedOct. 20, 1925A.

UNITED STATI-:s

. Y ANTONIN PASTBNAK, or vELKE-KUNCIGE, msm., czaelisnovei nnnnnveDEVICE non FURNAcEs.

v Application led February 7, 1923. Serial No. 617,623.

i frame, the blades being afterwards lifted from the grate andautomatically withdrawn from the furnace. y

The drawing shows a diagram of a design of the object of the invention.Fig. 1 being a longitudinal section ofthe furnace and feeding device,Fig. 2 a plan view of the same Fig, 3 a section `on the'line 3 3 ofFig. 1. Fig. 4 a section on the line 4-4 of F ig. 2. Fig. 5 afragmentary section of the fuel tank with the charging boX and Fig. -6 asection on the line 6-6 of Fig. 2.

The drawing shows the furnace as em ployed withv an internally firedboilerv Vithin the firing space 1 there arek grate bars 2 as well as afire plate of corresponding width. At the extremity of the grate ac'linker receptacle 4' is provided within the ash pit, which receptaclemay be pulled outward by means ofa chain drive 5. rlhe bottom of theclinker receptacle is formed by a trapdoor 6 which is hinged at thefront side as shown. Said trap door lwhen the said receptacle is withinthe ash pit lis supported' in a closed position by rails 1a. The rearwall of the clinker receptacle is indicated at 7. lVhen the receptacleis moved longitudinally through the ash pity to a point beyond the rearend thereof as indicated in dotted lines in Figure 1, the said bottom ortrap door 6 as it passes over the inner ends of the rails 1"nl drops bygravity andhence discharges the load of clinkers from the clinkerreceptacle. The furnace feeder proper consists of aframe 8 arranged andlongitudinally movable on rollers 9 which are mounted in bearings on anunderframe 10. To the frame `8 U-shaped conveyors or blades 11 arepivotally mounted at like intervals. One arm of each of these blades isin the shape of a double bell crank lever and pivoted to a through bar12 so that by shifting this said bar 12 all blades may be simultaneouslyturnedeither upwa-rtlsy ,0rv

downwards (Fig. The protruding l'end of thebar 12 is-connected toa'second-lever 13- carrying a counterweight V14e. l'oo'p12`a isonthe'bar 12 and is'for-'thefpurpose'of transmitting -motion from'. thelever l'ftosaid bar, while-permitting a certainfreedom of movement ofthelever 13 above' {its-pivotal a-Xis. Y f

The free end of the iframe Sreachign'g'iwell t into Vthe firey space 1-is provided `with afuel tank 15 the bottom of which isfitted Withhinged bottom flaps 16 -'swingingfsi1`nultaneously. Tothe underframeil()of the sliding' frame-8 a Achain'pulling device 117 is Afitted whichengages the frame Sfandis actuated "f3 i by thefdrive 18. The drive is;so designed as to render the speed of-tlieforward movement of the framelessithan the speed-of the back movement, as isV also usually the lcasewlth the well-knownf-planing machine drive. To the underframelOthereis also fitted, inclose proximity 5to the'fire space,`a coal hopper19 the bottom of which is curved as shown. This bottoml 20is kept closedby means of the lever-"21 andcounterweight-22. rThe underportion of thiscurved bottom ris fitted lwith a pin 23-which engages the wall of theholder 15 when Vthe latter is withdrawn fromI the fire boX, thusopening3the bottom and causing the lever 21 to raise the` weight 22. Y

This occurs every time the fuel holder is just beneath the hopper 19,the tsliding frame 8 being, at the same time, almost com pletelywithdrawny from the fire box, and v the blades'being in the position asindicated in Fig. 1 by dottedtlines and being keptin this position bytheguides in `the underframe. I V

As soon as the frame is moving in thev direction of the fire lspace .theround flap door 20,owing to the action of the weight 22, will close thelhopper 19, and thel fuel holder 15 supplied with the necessary fuelwill enterthe fire space. As soon as the back Hap 16 of the tank15,mounted on the 'pivot 25 and is releasedby the cam 24 fitted 1, machinesand the like.

short distance into the fire space by the blade 11 which happens to benext to it. As soon` as the frame is almost completely moved homeintothe lire space theV weight 14 butts againstv the vwall of the hopper19, and on final advancing movement of the frame S said lever 13 willswingover in the direction indicated b-y an arrow in Fig. 1, therebyexerting a rear pull on the bar 12 and hence lifting the blades from thegrate.

In Fig. 1 the end position of this swinging-over is shown in dashedlines. At this moment, the frame has altered its movement intothe firespace and is starting a quick movement in the opposite direction, viz,out from the fire space, by meansv of a reversing mechanism such as usedwith planning Aafter the frame has reached its end position in theunderframe the weight 11i, by means of a pin :Z6 fitted to the frame,Vis swung back into its initial position. The blades however, since."that they'are guided in the frame, and are unable to swing downwardowing to the cam 24, remain in their lifted position. Corresponding tothis end position the round flap lQ0 of the hopper 19 is swung overagainst the action of the weight Q2,

and freshV fuel enters the tank 15 from the hopper, Following this thedirection of movement is reversed, and the procedure as described aboverepeats itself. Here again the fresh fuel vis dropped on the front partof the grate, and4 then the frame is again pushed 'into the lire space 1till the last of the blades has passed the cam 24 when all bladeswillswing over in common towards i I. the grate. The last portion of coaldeposited 1 face of the grate with the fuel.

on the grate is again pushed forward by the. corresponding blade, thefuel pushed forward by the preceding process being also pushed forwardstill farther a certain distance by the next blade. Y

The drawing shows a furnace wherein five blades are provided for thepurpose of feeding the fuelto the fire box, accordingly it takesv tivefillings to cover the entire sur- Y The blade closest to the fuel tank15 serves to remove from A,the grate the already burned coal as well asthe slag formed during combustion, and to convey it to the slag box twhence it may be removed together with the rest of the ashes from theash pit. This method of firing is superior to the existing fire boxes inthat the fuel is fed absolutely automatically, and that the coal iscompletely uniformly vdistributed Vover the entire grate area, 'whiletheburntv coal and slag are at the same time automatically removed from thefire box. Besides this method offers the v advantage that it permits theuse of coal of low quality as well as of wet coal. As the coal issupplied to the fire space in^a number of consecutive impulses the coalfed'first to the grate is first dried on the front part of the latterand pre-heated, and it is only after this coal has been dried and heatedthat it is pushed further into the fire space andburned, fresh coalbeing supplied simultaneously. flue is indicated at v5() in Figure 1.

Havin now ascertained `and specified the nature o my invention, what Iclaim is:

1.y In combination with a furnace grate, a furnace feeder comprising aframe mounted for longitudinal movement above the grate, means to impartreciprocating movement to said frame, blades pivotally mounted onsaidframe, a bar connectedvto said,v

frame and arranged to 'open the bottom' of i the first hopper when thevframe is at one end. of its stroke, theI said second hopper having amovable bottom, and means to close the bottom of the second hopper as tthe latter reaches a position under the first hopper.

3. A furnace feeder comprising a fixed. hopper having a pivotallymounted bottom, a lever connected to said bottom and having acounterweight to normally hold said bottom in closed position, a framemounted,`

for longitudinal movement below said hopper, a second hopper carried bysaid frame and arranged to open the bottom of the first hopper when saidsecond hopper passes under the first hopper, said second hopper having amovable bottom, and means 'to close the movable bottom of the secondhopper as the latter moves under the first hopper.

In'witness whereof I affix my signature.

ANTONIN PASTRNK.

